The Distinction Between Endognathous and Ectognathous Insects Is a Distinction

The distinction between endognathous and ectognathous insects is a distinction between

A) diplurans, springtails, and proturans versus the rest of the insect orders.
B) holding the mandibles and maxillae internally in a pouch versus having external mouthparts.
C) adaptation for feeding on very small particles versus a wider ability to feed on larger food.
D) All of the choices are correct.
E) None of the choices are correct.